UAE eInvoice errors, rejections and statuses: how to find and fix them

Suppose your Accredited Service Provider (ASP) portal shows one invoice with the status "Rejected". That one word can point to four different problems:

• Your own system stopped the invoice before it left, because a field was missing or wrong.

• The buyer's ASP could not validate the invoice and sent it back.

• Your invoice was delivered, but your ASP has not received the Federal Tax Authority (FTA) confirmation for the tax data.

• The buyer received the invoice without any problem and then disputed the price or quantity.

Each problem has a different owner and a different fix. This guide explains how to tell them apart, what each UAE eInvoicing status means, and how to decide whether to correct, retry, resend or issue a credit note.

What should you check first when a UAE eInvoice fails?

Check where the invoice stopped before you change anything in it.

Under UAE eInvoicing, an invoice passes through five parties, called corners. The supplier is Corner 1 (C1). The supplier's ASP is Corner 2 (C2). The buyer's ASP is Corner 3 (C3). The buyer is Corner 4 (C4). The FTA is Corner 5 (C5). Section 5.1 of the UAE Electronic Invoicing Guidelines, version 1.1 (Guidelines v1.1) sets out the order of steps. For a full walkthrough, see how the 5-corner model works.

Work in this order: find the stage, then the type of error, then the action. If you skip the first step, two mistakes are common. One is sending an invoice again under a new number when the first one was actually delivered, which creates a duplicate. The other is treating a buyer's commercial dispute as a technical error and quietly issuing the invoice again.

Which confirmations does a UAE eInvoice produce?

What are the exchange MLS and the reporting MLS?

The Ministry of Finance (MoF) calls these confirmations Message Level Status (MLS) messages. There are two kinds: an exchange MLS about delivery, and a reporting MLS about the tax data. Guidelines v1.1 calls the same messages "electronic confirmations".

So a supplier normally receives two confirmations for each invoice: the exchange MLS and its own reporting MLS. The buyer's reporting MLS goes to the buyer.

Timing also matters. In the Guidelines' 11-step sequence, the buyer receives the invoice at step 6, before the FTA confirmations at steps 8 and 9. An invoice in the buyer's system does not prove that the tax data reached the FTA.

If the buyer's ASP cannot validate an invoice, it sends a negative MLS to the supplier's ASP and to the FTA. That is the most common "rejected" status.

What do the Peppol codes AP, AB and RE mean?

UAE eInvoices travel over the Peppol network, and many ASPs show exchange results using the response codes in OpenPeppol's MLS specification:

When the code is RE, a reason code explains why:

These are network codes, not UAE legal codes. Your ASP may also show its own, more detailed error messages. Those explain which rule failed inside an SV or BV result.

How is a technical rejection different from a buyer's dispute?

A negative MLS is a technical event. It means the file failed a check, an identifier did not match, or the ASP could not accept the message. It is not a customer complaint. Send it to systems, master data or tax.

A commercial dispute is different. The invoice was delivered without a problem, but the buyer disagrees with the price, the quantity or the service. The buyer's accounts payable (AP) team decides whether to approve, part-approve, hold or reject it. Send this to accounts receivable (AR) and sales.

Keep the two separate in your reports. If collections staff see a technical rejection as a customer objection, they will call the wrong person about the wrong problem.

What should you do for each eInvoice status?

This table links each status you may see to its likely cause, owner and next step.

What are the most common types of UAE eInvoice errors?

Structure, format and mandatory field errors

These happen when the buyer's ASP cannot read the XML file, a required PINT AE field is missing, or the document type does not fit the transaction. The PINT AE specification sets the structure and the required fields. The UAE eInvoice format guide lists the mandatory fields.

To find the cause, run the same file through your own pre-send check. If it fails in the same place, the problem is in your data. If it now passes, the earlier failure was probably temporary at the ASP.

Identifier and master data errors

These show up as a routing failure or an "unknown participant" message. Every business on the network has a Participant Identifier: scheme 0235 followed by its 10-digit Tax Identification Number (TIN). The TIN is the first 10 digits of any Tax Registration Number (TRN) the FTA has issued.

Common causes:

• A wrong or old TRN on the customer record.

• A tax group member's TIN taken from the group representative's TRN instead of its own.

• A buyer whose ASP has not yet created its Participant Identifier.

Three fixed addresses cover special cases. For a Tax Invoice to a buyer that has not joined eInvoicing yet, use 0235:9900000098 and also send the buyer a regular Tax Invoice by PDF or paper. For a deemed supply, the buyer address is 0235:9900000097. For an export where the buyer has no Peppol ID, use 0235:9900000099. For how identifiers are created, see UAE eInvoicing onboarding through EmaraTax.

Tax calculation and business rule errors

These are content problems. The tax category does not match the supply, VAT is charged on an exempt line, or the totals do not add up. Section 10.5 of Guidelines v1.1 lists six tax categories: standard rate, exempt, outside the scope of VAT, reverse charge, zero rated and margin scheme.

Check one line at a time. Which line failed? Which category does it use? Does that category match the actual supply? When totals do not add up, the cause is often two systems in your business calculating the same total in different ways.

Duplicate and retry errors

The buyer's ASP may reject an invoice as a duplicate. This usually happens when an invoice that was already delivered is sent again with the same details. The rejection protects both sides from a second invoice for the same supply.

Agree with your ASP how retries work before you go live. Ask whether a retry reuses the original invoice number and identifiers, and how the ASP flags a duplicate. Then build your system to match. Keep two actions separate: a retry sends the same document again after a temporary failure, and a correction needs a new document.

Connection and network errors

These include expired ASP credentials, a system that cannot be reached, or a timeout. Nothing in the invoice needs to change. Systems or the ASP owns the problem. Retry once the connection works, and use your ASP's support channel if it does not recover. Do not contact the customer about a connection failure.

If a technical fault stops you from issuing or receiving invoices, it may be a system failure that you must report to the FTA within two business days. See UAE eInvoicing system failure: reporting, fallback and recovery.

Invoices with no confirmation at all

Some invoices are sent and then nothing comes back: no confirmation and no error. Do not assume these will fix themselves. Set a time limit. Anything without a positive confirmation after that limit goes into your exception queue with an owner.

Should you correct, retry, resend or issue a credit note?

The right action depends on whether the invoice was delivered and whether the amount or tax treatment needs to change.

Guidelines v1.1 describes no way to edit an invoice after it has been delivered. Every correction after that point needs a new document. Ministerial Decision No. 243 of 2025, Article 6(2), requires an electronic credit note for cancellations, reduced amounts, returns and errors. For the full rules, see UAE eInvoicing credit notes.

A retry and a resend can look the same in a portal, but they are different. A retry sends the same document again after a temporary problem. A resend after a correction is a new document. Show them as two separate actions in your AR and AP tools, not as one "resend" button.

How do these fixes look in practice?

These examples are simplified to show the thinking. The details are generic.

A missing field, caught before sending. Your own check finds that the supplier's trade licence number is missing on an invoice from a subscription billing run. The invoice never leaves your system. Master data completes the field, and you release the same invoice. No credit note, no resend and no call to the buyer.

A wrong customer identifier. An invoice to a new customer comes back with a negative exchange MLS saying "unknown participant". Someone typed the customer's TIN by hand, and one digit is wrong. Master data corrects the TIN, and you send the invoice again. No credit note is needed, because the invoice was never delivered.

A delivered invoice with no reporting confirmation. The buyer's ASP confirms delivery, but your reporting MLS does not arrive. The buyer already has a valid invoice, so there is nothing to discuss with the customer. Tax and systems ask your ASP to resolve the reporting, and you log it under the same invoice number.

A duplicate after a retry. Your ASP retries an invoice after a timeout, and the buyer's ASP rejects the second attempt as a duplicate. The first attempt had been delivered. Keep the first delivery as the valid record and close the retry in your exception queue. Do not send it again under a new number.

A quantity dispute after delivery. All confirmations are positive, but the buyer's AP team disputes the quantity on one line. This is a commercial issue. Agree the correction with the buyer, issue a credit note (code 381) for the line, and issue a new invoice for the right quantity if the supply stands.

What should your eInvoice exception log record?

Every exception should record the same basic details. Without them, you cannot see which problems keep coming back.

Age every open exception from the first error, or from the time it was sent if nothing came back. Review anything older than your agreed limit. Each month, look at the three most common root causes. If one cause stays on top for three months, fix it at the source, usually the customer record, the item record or the tax setup, not in the queue.

Keep this evidence for as long as the invoice itself. For a taxable business, that is five years after the end of the tax period, or seven years for real estate. See UAE eInvoice retention periods and audit records.

Late invoices cost money. Under Cabinet Decision No. 106 of 2025, each eInvoice not issued and sent on time costs AED 100, up to AED 5,000 a month. Each late electronic credit note costs AED 100, up to a separate AED 5,000 a month. See UAE eInvoicing penalties for the full list.

Zoho Software Trading LLC is a Ministry of Finance-accredited eInvoicing service provider for the UAE, with accreditation number 121988, as shown on the MoF register of accredited service providers. Troubleshooting is faster when the invoice, its ASP transmission and its confirmations sit on the same record in your accounting system.

Explore UAE eInvoicing with Zoho Books

Frequently asked questions

What is a negative MLS in UAE eInvoicing?

It is a technical rejection. The buyer's ASP sends it when an invoice fails validation, and it goes to the supplier's ASP and to the FTA. On the Peppol network it usually appears as the code RE, with a reason code such as SV, BV or FD. It is not a commercial rejection by the buyer.

How many confirmations should a supplier receive for each eInvoice?

Two: the exchange MLS from the buyer's ASP, and the reporting MLS from the FTA for the tax data your own ASP reported. The buyer's reporting confirmation goes to the buyer.

Is a rejected eInvoice the same as a cancelled sale?

No. A negative confirmation means the invoice was not delivered or not reported. Whether the buyer still owes the amount depends on the contract, not on the network status.

Can you send the same eInvoice again after a rejection?

Yes, if it was never delivered. If your system blocked it or the buyer's ASP rejected it, fix the data and send it again. If it was delivered and later found to be wrong, issue a credit note, and a new invoice if the supply still stands.

Related guides

• How UAE eInvoicing works: the 5-corner model, end to end

• UAE eInvoicing credit notes: rules for correcting an Electronic Invoice

• UAE eInvoice format: PINT AE mandatory fields and XML structure

• UAE eInvoicing onboarding through EmaraTax: steps and identifiers

• AR eInvoicing in the UAE: issuing, tracking and correcting invoices